Equipment Information
As being one of the synthesizers in my collection, here follows some music production equipment information are mostly from Wikipedia, where you may even find further details.

Overview
- The Ion has several features that make it stand apart from other analog modeling synthesizers. Most importantly, it features a selection of emulations of classic analog filter models of synthesizers such as the Moog Minimoog, Oberheim SEM, the Roland TB-303, the ARP 2600 and the Roland Jupiter-8.[4] Besides these emulations (which carry euphemistic names due to trademark issues), it has a series of filter models that are not commonly found on most synthesizers, such as formant and comb filters. This vastly increases the sonic range; most virtual analogs have only a single multimode filter (usually featuring low-pass, high-pass and band-pass modes) which was either designed from scratch or “inspired by” an existing “famous” filter model. The fact that two of these filters can be used in a parallel or serial configuration adds to the sound design possibilities.
- Besides the selection of filters, it has an extensive modulation matrix. This allows the user to route a source (such as an LFO) to various targets with an adjustable intensity. The Ion’s extensive “Mod Matrix” rivals the routing options of some voltage-controlled modular synthesizers.
- While most virtual analog synthesizers are equipped with on-board effects, the Ion lacks two important ones; reverb and a long delay (the on-board delay only has 80ms of delay time). These are often used on synthesizers to add some atmosphere to what would otherwise be a “dry” sound.
- One feature that also sets it apart from other virtual analog synthesizers, is the high resolution of the endless rotating front panel knobs yielding a more precise real-time tweaking experience. This high resolution eliminates all “stair stepping” or quantization of parameter value changes. These are not encoders, but real endless potentiometers.
- The Ion’s keyboard has velocity sensitivity, but not aftertouch. However, the sound engine is capable of responding to both channel and polyphonic aftertouch messages received via MIDI. This feature means that with an external polyphonic aftertouch keyboard controller, the Ion can be made to modulate notes individually with finger pressure.[2]
Specifications
- Keyboard: 49 Velocity-Sensitive Synth-Action Keys.
- Polyphony: 8 voices.
- Multitimbral: 4 parts.
- Oscillators (per voice): 3 (Sine, Square-Pulse, Saw-Triangle waves) with wave shaping, FM, and hard/soft sync.
- Filters (per voice): 2 Multi-Mode Filters (16 types, including Moog, Oberheim emulations).
- Envelopes (per voice): 3 ADSR (Pitch/Mod, Filter, Amp).
- LFOs (per voice): 2 multi-wave LFOs + 1 Sample & Hold.
- Effects: 4 Insert Effects + Master Stereo FX (Chorus, Flanger, Delay, Distortion, etc.).
- Vocoder: 40-band built-in.
- Controllers: 30 knobs, 2 Mod Wheels, Pitch Wheel, Arpeggiator.
- Memory: 512 Patches, 64 Multi-Timbral Setups.
- Audio I/O: Stereo Outs, Stereo Outs (Balanced 24-bit), 2 Stereo Inputs.
- MIDI: In/Out/Thru.
- Release: Circa 2002-2003.
Availability
The Alesis ION is no longer in production, but can currently be found on Reverb ranging in price and condition, from $549 to $1000.